The invention relates to a bottle or container for containing liquid/gas and especially suited for transportation of samples thereof.
Duringn oil and gas production, automatic samplers are sent down to the well for collection of samples. The samples are transferred to transportation bottles which are sent to a laboratory for analysis. Samples from oil/gas-separators are also transferred to transportation bottles for transportation to the laboratory. Some samples are stored for many years, and these are meant to be stored in the transportation bottles under a fixed pressure.
It is very important that the bottles be clean, sterile and free of air to get representative samples. Previously, several different procedures were used to eliminate air from the bottles. The most common process is first to evacuate the bottles and then fill them up with mercury. When the oil/gas is filled into the bottle, the mercury will be replaced, and an extra bottle for collection of the mercury is necessary, since mercury is poisonous. Also, prohibition of use of mercury already has come into affect in some countries, and it is expected that use of mercury also will be forbidden in several other countries. Bottles filled with mercury are also very heavy to handle. The mercury also represents an investment.
Another method is just to evacuate the bottles by use of a vacuum pump. By this method one cannot be sure that all the air is removed from the bottle. Water has also been used to replace air in the bottles. By use of water a strange or foreign element is added to the sample. It is therefore an advantage to use water from the well where the sample was collected. This however is very bothersome.
Also known is a method where oil and gas are blown through the bottle until all air is removed and a representative sample is obtained. This is a bothersome and risky method, and it is, for example, not suited when a limited sample must be transferred.